Method of forging railway axles



June 20, 1950 v D. R. CORNELL METHOD OF FORGING RAILWAY AXLES s Sheets-Sheet 1 Filed NOV. 17, 1948 INVENTOR. DAM 0 2. C042 4 644 J1me 2Q, 1950 Filed NOV. 17, 1948 D. R. CORNELL 2,512,484

METHOD OF FORGING RAILWAY AXLES 3 Sheets-Sheet 2 INVENTOR. -D flA fl Q CUBA 54L Patented June 20, 1950 Dana R. Cornell, East Chicago, Ind., assignor to Standard Forgings Corporation, Chicago, Ill.-, a

corporation of Delaware Application November 1'7, 1948; Serial N 0. 60,520

' 6 Claims.

This invention relates to a new method of forging railway axles, and the application is a continuation-in-part of my co-pending application Serial No. 708,528, filed November 8 1946, now

abandoned, for Method and- Apparatus for Prod'uci'ng Forged Railway Axles.

Due to the heavy strain imposed on modern railway equipment, which must be relatively light to conform to high speed requirements and yet capable of carrying heavy loads, the demand for perfection in such equipment including axles is far beyond the requirements of the past. One of the essential requirements, for example, of the modern railway axles is substantial freedom from eccentricity. The Axle Research Committee of the A. A. R. has recommended that eccentricity of axles be limited to not to exceed inch, by which is meant not more than inch total throw in the body of the axles. Axle manufacturers have found that thistolerance cannot be adhered to in forged axles producedby methods now in use, and that when the eccentricity limitation is made a part of. the specifications, the forged axles must be machined, after forging, to meet the requirement.

Rough machining of the central portion of the as-forged' axle is the only means heretofore employed to obtain. the desired concentricity', and this is objectionable both to manufacturers and the railroads because of the added cost of the machining and the material taken off, and because. tool. marks from machine turning create another objectionable condition, namely, the forming of transverse ridges and valleys in the rough machined portion which contributes to fatigue failures in the axles so machined.

By the use of 'themethod and apparatus herein described, I am able to produce railway axles which have certain highly desirable qualities not heretofore attainable by known forging methods and apparatus. These qualitiesinclude-z' (1) close conformation in axle dimensions and contour to the specifications of the A. A. RL; (2) concentricity of the axle as forged and freedom from transverse concentric ridges and valleys such as result when thecenter is subjected to rough machining to obtain desired concentricity'; (3) elimination of all gouged out sections, chip marks, irregular surfaces and other surface defects which appearedin the billet; (4) finer grain and" su:- perior toughness of the metal of the finished forging; (5) continuous and undistorted longitudinally extending grain flow lines; and (6) uniformity of all axlesv produced by the method.

In. addition tothe improvements in axles produced by my method, other valuable results are attained. These include: (7) saving in metal; (8 saving in fuel required for heating the metal to forging temperature; (9) saving in heating and forging time; (10) saving in labor required; and (-11) saving in cost and time due to elimination of machining operations heretofore required.

An object of the invention is to produce, by forging, solid heavy duty railway axles having smooth forged tapered centers, the dimensions of the axles as forged being close tothose of the finished axles, whereby a substantial saving in billet weight and in machining operations is eifected'.

Another object of the invention is to provide positive means for forging axles of the character described which have diametrical roundness throughout their length, and are free from'eccentricity which exceeds the limit recommended b the Association of American Railroads. 1

It has been found in accordance with the present invention that an axle having the'desirable qualities hereinbefore outlined can be formed within a single heating to a relatively low temperature' by maintaining upon the billet, a positive continuous rotational torque, and a frequency of hammer operation of 50 to blows perminute while rotating the billet at a speed between Gland 11R; P..M. v

Preferably the speed and frequency of hammer blows should be close to the lower figure for initial forging steps andshouldapproach the upper. limit of speed. and frequency for the finish forging.

Thesavingl in fuel required for heating billets, and. the restriction of the forging temperature as hereinafter described, are important not only in the interests of economy but also because the lower the forging temperature is within plastic limits,. the liner and tougher the grain of the steel will be. It has been customary heretofore to-heat billets'to 2150 F; or more in order to complete v the: forgi g operationsat approximately 1750 F.,

without reheatingt Ihave been able, by my method, to reducethe heating to 2000 F., and to finish forge at approximately -1750 F. without reheating; Others have. attempted to produce forged? axles"frombilletsheated toless than 2150* F. by: methods differing from the one claimed herein, but have not been able to complete the forging without reheating or resorting to upsetting operations to complete theshaping. of the forged axle; Reheating is costly in time and fuel, and upsetting. operations,'after reheating,

forged temperature, so that finer grain size is as-' sured in each axle. In other words,-my process 2,512,484 i If 11-:

makes possible, for the first time, a commercially practical production of axles of the best quality including a more refined grain size.

By avoiding upsetting operations in my forged axles I maintain the uniform grain flow lines established by the forging operations in, longitudinallyextending unbroken and undistorted condition. Further, by avoiding the necessityof machining the smooth forged tapered centers, and by reducing to a minimum machining operations on the journals and wheel seats, I retain in the forged axles produced by my invention, the as forged outer layer of metal which experience has proved to be highly resistant to fatigue failure, produced by high speed forging of the entire billet, simultaneously, coupledwith continuous rotation of the billets and partially forged axles while they are supported on full length anvil dies. I

The means I have provided for rotating the forgings while they are being subjected to the forging blows of a steam drop hammer are such that the operation of the hammer is not slowed or interrupted by the rotating means. Heretofore the rotating or turning of the forging in a steam drop hammer has been accomplished in termittently, between hammer blows, either manly r y rnin device associated with and controlled by the operation of the reciprocating hammer or press. All these older methods require interruption of the forging operation, or relatively slow operation, in order to permit the turning means to function. My rotating means are independent of the forging mechanism, and 'c'ontinuous'in operation. The speeds of operation of the forging hammer and of the rotation imparting mechanism may be varied and controlled independently of each other. The rotary driving force is applied to one end of the billet or forging outwardly beyond one end of the forging dies, whereby it is possible for me to use axle impression dies provided with sub stantially closed ends for thermal forging step. This feature of construction not only aids in retaining forging temperature in the metal but also confines the metal and controls longitudinal movement thereof to the end that the die cavities are completely and compactly filled radially. This is important in attaining the close to specified contour of the axle, freedom from-gouged out surfaces, chip marks, and other irregularities which detract from the smooth forged surface required, and in obtaining the degree of concentricity and freedom fromeccentricity required by A. A. R. specifications, not heretofore attainable without machining and consequent increase in cost and waste.

Due to the use of the apparatus and method herein disclosed, production maybe increased from two. to three times the present rate of production without a corresponding increase in labor.

In the drawings:

Fig. 1 is a perspective view of apparatus employed in forging railway axles according to the method of my invention, showing the fioor plan and arrangement of the steam drop hammer and other apparatus but eliminating details of construction shown in other views Fig. 2 is a 'perspective view of a billet to be forged into axle form.

. Fig. 3 is an elevational, fragmentary view of the billet and tong-hold on one end thereof.

Fig. 4 is an elevational view of the forged axle as it appears at the end of the forging operation,

before the tong-hold and surplus end have been cut off.

Y Fig. 5 is a top plan view of the anvil die which comprises the corner rounding groove, the tapered center forming and lengthening groove and the axle impression groove.

Fig. 6 is a vertical, longitudinal sectional view of the tapered center forming and lengthening portion of the anvil die, taken in the plane of the line 6-6 of Fig. 5. g

Fig. 7 is a vertical transverse sectional view of hammer and anvil dies, detached from the drop hammer, the plane of the section being indicated by the dotted line T-! of Fig. 5. I I Fig.8 is a vertical transverse sectional view on an' enlarged scale, of the tapered center forming portion of the die, taken in the plane of the line 88ofFig.5. I I

Apparatus.The apparatus which I prefer to use in practicin'g my method of producing forged railway axles is arranged as shown inFig. 1. It comprises a continuous furnace I0 through which the billets II are moved, and a floor type manipulator l2 provided with billet gripping means l3 for conveying billets'll from the furnace l0 toa tong-hold press 14 located conveniently near the furnace. The tong-hold press l4 comprises cooperating upper and lower dies l5 between which one 'end of the billet is pressed to reduce the end and to form a tong-hold l6 as shown in Fig. 3. The dies l5 need not be provided with any special forming surfaces. The end of the billet is squeezed between the proximatefaces of the dies 15 and the tong-hold of reduced thickness is thus formed. The apparawe also comprises a steam drop hammer I1 located to receive billets from the tong-hold press l4, and a forging manipulator [8 located conveniently adjacent the steam drop hammer l! for the purpose of rotating the billets while they are being forged between the hammer dies.

The drop hammer I! is provided with an anvil die l9 and a reciprocating hammer die 20. These are mounted in the drop hammer by any well known means, such as the key 2l on anvil die l9 engaged in a groove in the'base 22 of the hammer and a'similar key on the hammer die 20 engaged by the reciprocating ram 23.v

The anvil die 19 comprises a corner-rounding groove 24, a tapered'center forming and lengthening groove: 25 andan axle impression groove 26.

The corner-roundin .-groove 24 is of uniform width, depth and cross sectional contour throughout the length of thegroove, which extends from end to endof the anvil die.

The tapered center forming and lengthening groove 25 .;is transversely concave as shown in Fig. 8 but'the ,curved floor ,of the groove is. inclined downwardly from the center 27: toward the opposite ends. of the dieas indicated'by the inclined surfaoeszfl, 28, Fig.,;6, which. are sub,

stantially complemental in .form'to the tapered center of the axle tobe produced.

The axleim-pressio'n groove 26 is contoured to be complemental to the axle to be forged and is adapted to receive a little less than one-half of the axle when horizontally disposed. In other Words, the depth of the axle impression groove 26 varies at diflerent points of its length and is slightly less than half of the diameter of the axle supported at a given point.- The axle impression' groove 26 in this embodiment of the invention is located between the grooves 24 and 25, and the ends of the groove -26 are substantially closed by end walls 29 provided with restricted openings. One end wall 29 is provided with a semicircular openingiiil'adapted to receive the lower half of the tong' hold 16 *on the axle end, and the other end wall 29 is provided with a semicircular opening 31 which serves as a gate for the surplus metal of the billet which is worked out through the die opening. Between'these ends 29, the axle impression groove is contoured to shape the axle to finished form, as indicated by the cavities 32, 33, 34, 35 and 36 which shape the collars, journals, wheel seats, tapered center portions and center, respectively.

The reciprocating hammer die preferably is contoured to correspond with the anvil die I9, but inverted with respect thereto, as shown in Fig. 7. However, it is not essential that the hammer die match the anvil die conformations exactly. Only the anvil die need be provided with the described grooves whereby the exact contour thereof is'imparted to the rotated billet or forging. When the billet is resting "in the groove 24 or the groove 25, th cooperating dies i9 and 20 are spaced apart to a greater extent than is indicated in Fig. 7, but when the partially formed axle is supported in the axle impression groove 26 the cooperating dies approach each otheras indicated in that figure.

The cavity formed by the axle impression groove 26 of the anvil die I9 and the axle impression groove of the hammer die 20 corresponds in dimensions and contour to the axle to be formed. as shown in Fig. 4, wherein the axle, at the end of the forging operation, comprises collars 37, journals 38, wheel seats 39, tapered center portions 40, center 41, the tong-hold is at one end and surplus 42 at the opposite end.

Reverting to Fig. 1, the manipulator [8 'comprises mechanism for imparting continuous rotary motion in either direction to the billet, at selected speeds up to 11 R. P. M., preferably between '6 and 11 R. P. M., and means for moving the mechanism support relatively to the drop hammer for convenient handling of the billets by the manipulator.

Preferably the manipulator comprises a platform 43 movable longitudinally of the support ing rails 44, 44, the latter being adj ustably positioned in .cross rails M5, #5 adjacent the drop hammer H. The platform 43 supports a housing 43"whic-h encloses any suitable power transmission mechanism for imparting rotary motion in either direction to the shaft '45 on which are mounted the gripping jaws 41 {for engaging the billet tong-hold it. The shaft 46 and jaws 4'? are movable axially of the shaft with platform 43, and vertically by independent means, to move the jaws toward and away from the hammer as required for engaging and disengaging the tong-hold and positioning the billet in the dies. Since the details of construction of the rotary motion impart-ing mechanism and the 6 reciprocating mechanism for moving the shaft 46 longitudinally do not constitute the subject matter of this invention and may be varied, it is believed unnecessary to show the same.

Suffice to say that any speed controlled continuous rotary motion transmission mechanism, capable of rotating a billet-of axle weight while resting on "an anvil die, and provided with clutch slipping means which becomes operative when the rotative movement of the billet is retarded for a fractional part of a second dueto hammer and billet contact, will serve the purposes of this part of the apparatus.

Mathilde-The first step in my method is the selection of a billet such as the billet ll shown in Fig. '1. This billet has a cross sectional form consisting of a square with rounded corners. The lengthof the billet is regulated by the weight requiredto make the axle of the desired dimensions.- For example, to produce a standard 6" x 11" A. A. R. freight car axle, I employ a billet having an average weight of 1M0 lbs. and a minimum weight of 1110 lbs., approximately '77 inches long and 7 wide and deep; that is, thesc'ross' sectional dimensions of the round cornered square are 7%, x 7 /4". In methods heretofore employed, the weight of the billet re" quired for the same freight car axle was 1185 lbs. average, 1160 lbs. minimum; size of the square 8 /2"-'x 8 and length approximately 58 inches.

Next the billets are heated in a continuous furnace such as shown at l-fl in Fig. 1, according to well known methods, being moved at required intervals, one at a time, through the length of the furnace. Instead of heating to 2156" F., as heretofore in order to finish forge While the metal remains sufficiently plastic, which requires a temperature of approximately 1750" 52, my method requires heating to only 2000 F. in order to finish forge at said temperature of 1750" F. without reheating. The achievement of the complete forging operation within the temperature range of 2000 F. to 1750" F, whereby substan tial savings in production cost and superior quality of productare attained, is made possible by carrying out the following described steps at a high rate of speed and in quick succession.

After the heating to approximately 2000 F. as described, the hot billet is picked up by means of the floor type manipulator l2 and carried to thepress M for making the tong-hold it on one end of the billet l i. This is done by squeezing in a series of strokes about three inches at one end of the billet between the dies l5 'to'a smaller cross section, whereby .a tong-hold 10 inches long and 4 by 4 inches in width is produced.

Heretofore, in the forgingof railway axles, the billet has been turned manually orby means of mechanism such as tongs or lifters associated with the ramof the forging hammer or press. Such methods and deviceshave resulted in intermittent rotation or in slowing or interrupting the operation of the forging machinery. Rotary motion has also been imparted to the work in various kinds of metal working operations such as grinding, polishing, swaging and the like, through means suchas head and tail stocks which engaged opposite ends of the work while the grinding, polishing, etc, was being done. Many o'fth'ese operations have been directed to articles such as shafts, shells, rolls and the like. In the axle forging field, turning devices have been applied to the ends of billets, unreduced in cross sectional dimensions, or to intermediate portions. It has not been proposed, heretofore, to "reduce a small portion of the billet, at one end, say about three inches, to form a reduced tong-hold of approximately ten inches, accessible exteriorly of the anvil and hammer dies, for actuation by rotary motion imparting mechanism entirely independent of the hammer operation. This independence of the rotary motion imparting mechanism obviates all interruption of the forging apparatus and permits the rate of application of the forging blows to be varied and to be gradually increased in succeeding steps of the forging operation.

Forming the tong-hold Id of relatively small cross section as compared to the diameter of the billet, whereby the billet can be rotated substantially continuously at desired speeds by means independent of the forging apparatus and in a manner which does not require interruption of or interference with the high speed operation of the hammer, is an important feature of my method, as will be understood from a description of the whole procedure.

The floor type manipulator l2 grips the tonghold and places the billet lengthwise in the groove 24 of the anvil die l9 to be worked on by the drop hammer die 20 for rounding the corners of the billet. Since the groove 24 is of uniform cross sectional contour, the billet need not be centered between the groove ends. The manipulator 18, by means of its jaws 41, engages the tong-hold is of the hot billet and rotate the billet during the coner rounding and succeeding steps of the forging operation.

The manipulator shaft 45, carrying the jaws 41, is continuously rotated in a clockwise or counterclockwise direction by the power driven mechanism in the housing 44, at any desired speed, preferably between 6 and 11 R. P. M. The application of the rotative driving force on the shaft 46 is continuous. Any suitable power, motor or other, drives the mechanism in the housing 44. The continuous rotary motion is transmitted to the billet ll through the tong-hold l6 gripped in the jaws 41, and the billet is rotated at selected manipulator speed, as it rests on the anvil die l9, throughout the forging operation excepting during the fractional part of a second when the rotation is retarded by contact of the hammer die 20 with the billet. During this fractional part of a second, slipping takes place in the manipulator tong clutch or between the billet tong-hold and manipulator jaws 41.

Preferably, for the corner-rounding operation in the anvil groove 24, I employ rotation of the billet at manipulator speed of 7 R. P. M. and hammer operation at a rate of 60 blows per minute for a period of 15 seconds.

Next the rounded billet is moved to the groove 25 of the anvil die IQ for performing the step of reducing the cross sectional dimensions of the billet and making the center portion thereof assume approximately the final shape of the tapered center of the railway axle at this point. The surfaces 2! and 28 of the anvil portion 25 of the die are contoured to impart the desired tapered form to the center portion of the billet. The effect of the hammer die striking the billet while thus supported on the anvil while being rotated about its longitudinal axis increases the length of the billet to nearly the length of the finished axle.

Preferably, for this forming of the tapered center and lengthening of the billet, I employ rotation of the billet at manipulator speed of 7 R. P. M. and hammer blows delivered at the rate. of 60 per minute for a period of seconds.

When the billet has thus been reduced in cross sectional dimensions to approximately the final shape of the axle in its central tapered portion, and lengthened to nearly the finished axle length, it is moved to the axle-impression portion 26 of the die I!) where the hammer die 20 strikes the hot metal and still further lengthens the stock and rounds it so that the die is completely filled.

The axle impression groove 26 in the lower die 19 is arranged so that the tong-hold 16 on the billet extends beyondthe die wall 29 and can be grasped by the manipulator jaws 41. At the opposite end the gate 3| receives the surplus stock 42 as it is worked out by the forging strokes of the hammer. Th exact contour of each part of the axle need be maintained only in the bottom half 26 of the cooperating upper and lower dies. Since the hammer or upper die 20 strikes the heated billet while it is being rotated substantially,

continuously about its axis and is supported on the lower die, said die imparts to the billet its intended form closely approximating the finished axle design. I

Preferably, for this finish forging, that is, the shaping of the forging closely to finished axle form, I employ rotation of the billet at manipulator speed of 10 R. P. M. and hammer blows delivered at the rate of per minute for a period of seconds.

Preferably the manipulator rotation is varied to maintain rotation at the rate of approximately one-eighth of, a revolution of the billet per blow of the hammer die.

A full sized standard railway axle can be produced efliciently and economically by this method in a 25,000 lb. steam drop hammer, with the savings in weight of stock and in fuel required for heating, as well as the other advantages heretofore described. The average forging time in seconds, per forging, in production of a standard 6 x ll railway axle, is 110 seconds in the finish groove 26 and 165 seconds for the complete furnace to floor time procedure. The average number of hammer blows on the billet in the finish groove is and the average total number of hammer blows per forging is 190.

The successive forging steps are applied to the entire body of the billet during each step, and thus the grain flow lines established in the billet are maintained throughout the process. The grain flow lines nearest the surface follow its contour but those within the body of metal are substantially parallel to the axis of the axle. The uniform working of the entire body of the metal by each forging stroke, through pressure applied laterally of the longitudinal axis of the billet, produces an axle of superior quality and durability.

Substantially continuous rotation of the billet, coupled with speedyand uninterrupted hammer operation, with forging blows delivered to the entire billet simultaneously, all contribute to achievement of the objects of my invention, namely: the completion of the forging operation without reheating within the narrow temperature range of 250 F. with a top limit of approximately 2000 F., whereby economy in production and superior fineness and toughness of metal in the forged axles are assured.

Further, these method steps including the forging steps of forming the smooth tapered center, followed by forging to finished axle form,

with substantially continuous rotation, while controlling the lengthening of the billet, insure radial compactness and a. high degree of concentricityin the'finished axles without added machining. of the asforged. axles.

To finish the forged axle,-the tong-hold llrand the surplus-stock. 42 at opposite. ends of, the forsing are cut off, and a-minimum of machining is required to reduce by machiningthe journals and wheel seats to predetermined size and contour. 1 s i The described method produces railway axles having fine grain structure, and this denotes superior quality and toughness, and less tendency of the metal to rupture or break under strains, a compared to coarser grained structures found in specimens produced from metal heated to 2.150 R, or to the higher-temperatures generally employed heretofore. The grain. structure of asforged steel, after cooling from forging temperatures without subsequent heat treatment, is non-uniform; however, the grain sizes in the -metal of axles produced by mymethod are substantially finer or smaller than those in axles produced from billets heated to 2150" F. or more. The largest individual grain in the 2000 F; specimen is considerably-smaller than the largest individual grain found in a 2150 F. specimen.

The as-forged grain condition is affected by chemical characteristics of metal, heat characteristics, holding time at forging temperatures, amount of reduction in forging-and rate of cooling; but when these factors are equal in methods which difier only as. to the heating of the billet, to 2000" F. or 2150 the grain structureof the lower temperature specimen is substantially finer and its toughness substantially greater than the higher temperature specimen.

The method described, including the forging of the rotated billet simultaneously throughout its length, in circumferential increments successively exposed to hammer blows, results in the production .of uniform metal structure both around the circumference of the axle and throughout its length. The fact that the billet is axially stationary during the forging and subjected to blows from end to end simultaneously while being rotated, aids in concentric contour shaping and forming a tough unbroken outer layer of metal on the surface of the axle, readily distinguishable from the non-uniform structure and irregular surface of the forgings produced by methods which involve lifting of the billet and non-continuous rotation and interrupted forging of the billet. This tough, unbroken outer layer is M; to, /4 inch thick. l i

This method enables mejtoproduce railway axles of various contours and sizes, and the apparatus described may be adapted for such purpose by obvious changes in the axle-impression contour 26 of the bottom die I 9, and without departing from the scope of my invention as set forth in the appended claims.

I claim:

1. The method of producing a solid heavy duty forged railway axle having a smooth forged tapered central portion and wheel seats, journals and collars at opposite sides of said portion, which comprises the steps of selecting a billet having cross sectional dimensions slightly greater than the diameter of the wheel seats of the axle to be forged and weighing only slightly more than the finished axle, heating the billet to approximately 2000 F., reducing one end of the billet to form a rotary driving connection, subjectingthe billet to continuous rotational torque from said reduced end, forging the billet laterally of its longitudinal axis simultaneously with the application of rotational torque thereto while shaping and lengthening certain longitudinal portions of the billet to substantially finished axle form, and thereafter subjecting the entire partially formed billet to a second forging operation While imparting continuous rotational torque thereto to shape. it into axle form closely approximating the final design of thefinished axle, wherein said'forming of the rotary drivingconnection, forging and billet rotating operations are rapidly completed without reheating of the billet and the billet is forged to substantially finished axle form atapproximately 1750 F.

2. The method of producing a. solid heavy duty concentrically forged railway axle having a smooth forged tapered central portion and wheel seats, journalsand collars at opposite sides of said portion, which comprises the steps of selecting a billet having cross sectional dimensions slightly greater than the diameter of the wheel seats of the axle to-be forged and weighing only slightly more than thefinished axle, heating the billet to approximately 2000 Ft, reducing one end of'the billet to form a rotary driving connection, subjecting the billet to continuous rotation from said reduced end, forging. the billet'laterally of its longitudinal axis simultaneously with the application of said rotary motion thereto while shaping and lengthening certain'longitudinal portions of the billet to substantially finishedaxle form, and thereafter subjecting the entire partially formed billet to a second forging operation while imparting continuous rotary motion. thereto and limiting the extent of lengthwise movement of the metal of the billet 'to-shape it. into concentric smooth forged axle form closely approximating'the final design of the finished axle, wherein. said forming of the rotary driving connection, forging and billet rotating operations are rapidly completed without reheating of the billet and the billet is forged to substantially finished axle form at approximately 1'750" F;

3. The method of producing a solid heavy duty forged railway axle having a smooth forged ta,- pered central portion and wheel seats, journals, and collars at opposite, sides of said portion, which comprises the steps of selecting a billet having cross sectional dimensions slightly greater than the diameter of the wheel seats of. the axle to be forged and weighing only slightly more than the finished axle, heating the billet to approximately 2000 F., reducing one end of the billet to form a rotary driving connection, applying. to said reduced end a continuous rotational driving torque to thereby-produce substantially continuous rotation, striking said billet during said rotation with afidrophammer to thereby forge the billet laterally of its: longitudinal axis {simultaneously with the appplication of said rotational-torque thereto while shaping and lengthening certain longitudinal portions of the billet to substantially finished axle form, and thereafter subjecting the entire partially formed-billet-to asecond forging operation while imparting continuous rotational mately in the ratio of one to eight, and'the entire forging operations being completed'withou'tire 1 l heating within'a range of temperature between approximately 2000 F. and 1750" F.

4. The method of producing a solid heavy duty forged railway axle having a smooth forged tapered central portion and wheel seats, journals,

and collars at opposite sides of said portion, which comprises the steps of selecting a billet having cross sectional dimensions slightly greater than the diameter of the wheel seats of the axle to be forged and weighing only slightly more than Y billet laterally of its longitudinal axis simulu. 'taneously with the application'of said rotational torque thereto while shaping and lengthening certain longitudinal portions of the billet to substantially finished axle form, thereafter subjecting the entire partially formed billet to a second forging operation while imparting continuous rotational torque thereto to thereby produce substantially continuous rotation of between 9 and 11 R. P. M.-and striking said billet during said rotation with a drop hammer at a frequency between approximately 70 and 90 blows per minute to shape it into axle form closely approximating the final design of the finished axle, the striking action of said hammer and the rotation of said billet being such that the-entire operation is completed without reheating within a, range of temperature between approximately 2000 F. and 1750 F.

5. The methodof producing a solid heavy duty forged railway axle having a smooth forged tapered central portion and wheel seats, journals, and collars at opposite sides of said portion, which comprises the steps of selecting a billet having cross sectional dimensions slightly greater than the diameter of the wheel seats of the axle to be forged and weighing only slightly more than the finished axle, heating the billet to approximately 2000 F., reducing one end of the billet to form a rotary driving connection,

applying to said reduced end a continuous rotational driving torque to thereby produce substantially continuous rotation, striking said billet during said rotation with a drop hammer to thereby-forge the billet laterally of its longitudinal axis simultaneously with the application of said rotational torque thereto while shaping and lengthening certain longitudinal portions of the billet to substantially finished axle forms, and thereafter supporting said billet throughout its length, ands'ubiecting the entire partially formed billet to a second forging operation laterally of its longitudinal axis while restricting the lengthwise movement of the metal of the partially forged billet and while imparting continuous rotational torque thereto to shape it into axle form closely approximating the final design of the finished axle, the striking action of said hammer and the rotation of said billet being increased in speed during the respective forging operations, the number of rotations per minute and the number of hammer blows per minute being approximately in the ratio of one to eight, so that the entire operation is completed without reheating within a range of temperature between approximately 2000 F. and 1750 F.

6. The method of producing a solid heavy duty forged railway axle having a smooth forged tapered central portion and wheel seats, journals, and collars at opposite sides of said portion, which comprises the steps of selecting a billet having cross sectional dimensions slightly greater than the diameter of the wheel seats of the axle to be forged and weighing only slightly more than the finished axle, heating the billet to approximately 2000 F., reducing one end of the billet to form a rotary driving connection, applying to said reduced end a continuous rotational driving torque to thereby produce substantially continuous rotation of between 6 and 9 R. P. M., striking said billet during said rotation with a drop hammer at a frequency between approximately and blows per minute to thereby forge the billet laterally of its longitudinal axis simultaneously with the application of said rotational torque thereto while shaping and lengthening certain longitudinal portions of the billet to sub stantially finished axle form, and thereafter sup porting said billet throughout its length and subjecting the entire partially formed billet to a second forging operation laterally of its longitudinal axis while restricting the lengthwise movement of the metal of the partially forged billet and while imparting continuous rotational torque thereto to produce substantially continuous rotation of between 9 and 11 R. P. M. and striking said billet during said rotation with a drop hammer at a frequency between approximately '70 and blows per minute, to shape it into axle form closely approximating the final design of the finished axle, the striking action of said hammer and the rotation of said billet being gradually increased in speed during the respective forging operations, so that the entire operation is completed without reheating within a range of temperature between approximately 2000 F. and 1750" F.

DANA R. CORNELL.

No references cited. 

